In conventional test sections for wind tunnels, it is sometimes desirable to obtain test data at various positions around the test device. It is necessary to provide apparatus to obtain the test data which will not cause undesirable flow disturbances within the test section.
In one prior art test system, the test device is mounted upon a movable support. This requires a complex configuration to provide apparatus which will permit movement of the test apparatus without causing undesirable flow disturbances within the test section.
It has been suggested that slots with movable closure elements be provided to permit movement of probes within a test section. It is difficult to provide a movable closure element that will not cause undesirable flow disturbances in the test section.